tpm/tpm.c

   1 /*
   2  * TPM configuration
   3  *
   4  * Copyright (C) 2011-2013 IBM Corporation
   5  *
   6  * Authors:
   7  *  Stefan Berger    <stefanb@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  *
  12  * Based on net.c
  13  */
  14 #include "config-host.h"
  15
  16 #include "monitor/monitor.h"
  17 #include "qapi/qmp/qerror.h"
  18 #include "tpm_int.h"
  19 #include "tpm/tpm.h"
  20 #include "qemu/config-file.h"
  21 #include "qmp-commands.h"
  22
  23 static QLIST_HEAD(, TPMBackend) tpm_backends =
  24     QLIST_HEAD_INITIALIZER(tpm_backends);
  25
  26
  27 #define TPM_MAX_MODELS      1
  28 #define TPM_MAX_DRIVERS     1
  29
  30 static TPMDriverOps const *be_drivers[TPM_MAX_DRIVERS] = {
  31     NULL,
  32 };
  33
  34 static enum TpmModel tpm_models[TPM_MAX_MODELS] = {
  35     -1,
  36 };
  37
  38 int tpm_register_model(enum TpmModel model)
  39 {
  40     int i;
  41
  42     for (i = 0; i < TPM_MAX_MODELS; i++) {
  43         if (tpm_models[i] == -1) {
  44             tpm_models[i] = model;
  45             return 0;
  46         }
  47     }
  48     error_report("Could not register TPM model");
  49     return 1;
  50 }
  51
  52 static bool tpm_model_is_registered(enum TpmModel model)
  53 {
  54     int i;
  55
  56     for (i = 0; i < TPM_MAX_MODELS; i++) {
  57         if (tpm_models[i] == model) {
  58             return true;
  59         }
  60     }
  61     return false;
  62 }
  63
  64 /*
  65  * Write an error message in the given output buffer.
  66  */
  67 void tpm_write_fatal_error_response(uint8_t *out, uint32_t out_len)
  68 {
  69     if (out_len >= sizeof(struct tpm_resp_hdr)) {
  70         struct tpm_resp_hdr *resp = (struct tpm_resp_hdr *)out;
  71
  72         resp->tag = cpu_to_be16(TPM_TAG_RSP_COMMAND);
  73         resp->len = cpu_to_be32(sizeof(struct tpm_resp_hdr));
  74         resp->errcode = cpu_to_be32(TPM_FAIL);
  75     }
  76 }
  77
  78 const TPMDriverOps *tpm_get_backend_driver(const char *type)
  79 {
  80     int i;
  81
  82     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
  83         if (!strcmp(TpmType_lookup[be_drivers[i]->type], type)) {
  84             return be_drivers[i];
  85         }
  86     }
  87
  88     return NULL;
  89 }
  90
  91 #ifdef CONFIG_TPM
  92
  93 int tpm_register_driver(const TPMDriverOps *tdo)
  94 {
  95     int i;
  96
  97     for (i = 0; i < TPM_MAX_DRIVERS; i++) {
  98         if (!be_drivers[i]) {
  99             be_drivers[i] = tdo;
 100             return 0;
 101         }
 102     }
 103     error_report("Could not register TPM driver");
 104     return 1;
 105 }
 106
 107 /*
 108  * Walk the list of available TPM backend drivers and display them on the
 109  * screen.
 110  */
 111 void tpm_display_backend_drivers(void)
 112 {
 113     int i;
 114
 115     fprintf(stderr, "Supported TPM types (choose only one):\n");
 116
 117     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
 118         fprintf(stderr, "%12s   %s\n",
 119                 TpmType_lookup[be_drivers[i]->type], be_drivers[i]->desc());
 120     }
 121     fprintf(stderr, "\n");
 122 }
 123
 124 /*
 125  * Find the TPM with the given Id
 126  */
 127 TPMBackend *qemu_find_tpm(const char *id)
 128 {
 129     TPMBackend *drv;
 130
 131     if (id) {
 132         QLIST_FOREACH(drv, &tpm_backends, list) {
 133             if (!strcmp(drv->id, id)) {
 134                 return drv;
 135             }
 136         }
 137     }
 138
 139     return NULL;
 140 }
 141
 142 static int configure_tpm(QemuOpts *opts)
 143 {
 144     const char *value;
 145     const char *id;
 146     const TPMDriverOps *be;
 147     TPMBackend *drv;
 148
 149     if (!QLIST_EMPTY(&tpm_backends)) {
 150         error_report("Only one TPM is allowed.\n");
 151         return 1;
 152     }
 153
 154     id = qemu_opts_id(opts);
 155     if (id == NULL) {
 156         qerror_report(QERR_MISSING_PARAMETER, "id");
 157         return 1;
 158     }
 159
 160     value = qemu_opt_get(opts, "type");
 161     if (!value) {
 162         qerror_report(QERR_MISSING_PARAMETER, "type");
 163         tpm_display_backend_drivers();
 164         return 1;
 165     }
 166
 167     be = tpm_get_backend_driver(value);
 168     if (be == NULL) {
 169         qerror_report(QERR_INVALID_PARAMETER_VALUE, "type",
 170                       "a TPM backend type");
 171         tpm_display_backend_drivers();
 172         return 1;
 173     }
 174
 175     drv = be->create(opts, id);
 176     if (!drv) {
 177         return 1;
 178     }
 179
 180     QLIST_INSERT_HEAD(&tpm_backends, drv, list);
 181
 182     return 0;
 183 }
 184
 185 static int tpm_init_tpmdev(QemuOpts *opts, void *dummy)
 186 {
 187     return configure_tpm(opts);
 188 }
 189
 190 /*
 191  * Walk the list of TPM backend drivers that are in use and call their
 192  * destroy function to have them cleaned up.
 193  */
 194 void tpm_cleanup(void)
 195 {
 196     TPMBackend *drv, *next;
 197
 198     QLIST_FOREACH_SAFE(drv, &tpm_backends, list, next) {
 199         QLIST_REMOVE(drv, list);
 200         drv->ops->destroy(drv);
 201     }
 202 }
 203
 204 /*
 205  * Initialize the TPM. Process the tpmdev command line options describing the
 206  * TPM backend.
 207  */
 208 int tpm_init(void)
 209 {
 210     if (qemu_opts_foreach(qemu_find_opts("tpmdev"),
 211                           tpm_init_tpmdev, NULL, 1) != 0) {
 212         return -1;
 213     }
 214
 215     atexit(tpm_cleanup);
 216
 217     return 0;
 218 }
 219
 220 /*
 221  * Parse the TPM configuration options.
 222  * To display all available TPM backends the user may use '-tpmdev help'
 223  */
 224 int tpm_config_parse(QemuOptsList *opts_list, const char *optarg)
 225 {
 226     QemuOpts *opts;
 227
 228     if (!strcmp(optarg, "help")) {
 229         tpm_display_backend_drivers();
 230         return -1;
 231     }
 232     opts = qemu_opts_parse(opts_list, optarg, 1);
 233     if (!opts) {
 234         return -1;
 235     }
 236     return 0;
 237 }
 238
 239 #endif /* CONFIG_TPM */
 240
 241 static const TPMDriverOps *tpm_driver_find_by_type(enum TpmType type)
 242 {
 243     int i;
 244
 245     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
 246         if (be_drivers[i]->type == type) {
 247             return be_drivers[i];
 248         }
 249     }
 250     return NULL;
 251 }
 252
 253 static TPMInfo *qmp_query_tpm_inst(TPMBackend *drv)
 254 {
 255     TPMInfo *res = g_new0(TPMInfo, 1);
 256     TPMPassthroughOptions *tpo;
 257
 258     res->id = g_strdup(drv->id);
 259     res->model = drv->fe_model;
 260     res->type = drv->ops->type;
 261     res->tpm_options = g_new0(TpmTypeOptions, 1);
 262
 263     switch (res->type) {
 264     case TPM_TYPE_PASSTHROUGH:
 265         res->tpm_options->kind = TPM_TYPE_OPTIONS_KIND_TPM_PASSTHROUGH_OPTIONS;
 266         tpo = g_new0(TPMPassthroughOptions, 1);
 267         res->tpm_options->tpm_passthrough_options = tpo;
 268         if (drv->path) {
 269             tpo->path = g_strdup(drv->path);
 270             tpo->has_path = true;
 271         }
 272         if (drv->cancel_path) {
 273             tpo->cancel_path = g_strdup(drv->cancel_path);
 274             tpo->has_cancel_path = true;
 275         }
 276         break;
 277     case TPM_TYPE_MAX:
 278         break;
 279     }
 280
 281     return res;
 282 }
 283
 284 /*
 285  * Walk the list of active TPM backends and collect information about them
 286  * following the schema description in qapi-schema.json.
 287  */
 288 TPMInfoList *qmp_query_tpm(Error **errp)
 289 {
 290     TPMBackend *drv;
 291     TPMInfoList *info, *head = NULL, *cur_item = NULL;
 292
 293     QLIST_FOREACH(drv, &tpm_backends, list) {
 294         if (!tpm_model_is_registered(drv->fe_model)) {
 295             continue;
 296         }
 297         info = g_new0(TPMInfoList, 1);
 298         info->value = qmp_query_tpm_inst(drv);
 299
 300         if (!cur_item) {
 301             head = cur_item = info;
 302         } else {
 303             cur_item->next = info;
 304             cur_item = info;
 305         }
 306     }
 307
 308     return head;
 309 }
 310
 311 TpmTypeList *qmp_query_tpm_types(Error **errp)
 312 {
 313     unsigned int i = 0;
 314     TpmTypeList *head = NULL, *prev = NULL, *cur_item;
 315
 316     for (i = 0; i < TPM_TYPE_MAX; i++) {
 317         if (!tpm_driver_find_by_type(i)) {
 318             continue;
 319         }
 320         cur_item = g_new0(TpmTypeList, 1);
 321         cur_item->value = i;
 322
 323         if (prev) {
 324             prev->next = cur_item;
 325         }
 326         if (!head) {
 327             head = cur_item;
 328         }
 329         prev = cur_item;
 330     }
 331
 332     return head;
 333 }
 334
 335 TpmModelList *qmp_query_tpm_models(Error **errp)
 336 {
 337     unsigned int i = 0;
 338     TpmModelList *head = NULL, *prev = NULL, *cur_item;
 339
 340     for (i = 0; i < TPM_MODEL_MAX; i++) {
 341         if (!tpm_model_is_registered(i)) {
 342             continue;
 343         }
 344         cur_item = g_new0(TpmModelList, 1);
 345         cur_item->value = i;
 346
 347         if (prev) {
 348             prev->next = cur_item;
 349         }
 350         if (!head) {
 351             head = cur_item;
 352         }
 353         prev = cur_item;
 354     }
 355
 356     return head;
 357 }